Field replaceable battery pack and lift counterbalance for a mobile manipulation robot

ABSTRACT

Systems and methods for improved power supply and use in a battery powered device, such as a mobile manipulation robot, are disclosed. These systems include field replaceable batteries that may be hot-swapped with no robot downtime, methods for automating battery replacement messaging and robot operation when battery power is low, and improved mechanical systems having lower energy requirements, and thus extending the lifetime of the battery operated mobile manipulation robot.

RELATED APPLICATIONS

This application claims the benefit under 35 U.S.C. §119(e) of priorU.S. Provisional Patent Application Ser. No. 62/408,187, filed on Oct.14, 2016, the entire content of which is hereby incorporated byreference.

TECHNICAL FIELD

The present invention relates generally to systems and methods forbattery exchange and power conservation in a robotic device.

BACKGROUND

The recent development of robotic devices, and in particular autonomousrobotic devices which use battery power, has been significant. Thesedevices find use in a large number of environments, and are configuredto perform a wide range of functions. For example, small battery poweredcleaning robots, such as detailed in U.S. Pat. Nos. 7,031,805 and9,550,294, are configured to vacuum floors in residential and smallcommercial settings. These robots include batteries which may berecharged when the robot docks with a charging station. In general,these small robots are able to complete their assigned tasks on a singlebattery charge, and thus the down-time associated with recharging doesnot pose a problem (i.e., the battery is recharged before the floorsneed to be cleaned again).

Larger systems, such a humanoid robots, robots configured to restockinventory, and robotic vehicles which perform in hazardous environments,are generally larger, and therefore have greater power requirements. Assuch, they may not be able to complete an assigned task on a singlebattery charge. Moreover, their assigned tasks may be open-ended suchthat any down-time would represent an impediment. For example, inlogistics facilities, such as distribution centers or retail stores,goods are constantly being put-away (stocked or shelved) and picked(retrieved from the shelves). Since these robots are generallyexpensive, most facilities limit their total number. As such, thedowntime required to charge a robot working in such a facility wouldrepresent a significant delay in the flow of goods within the facility.

Previous solutions to such a problem include the exchange of dischargedbatteries for fully charged batteries. For example, U.S. PatentApplication Publication No. 2011/0005846 describes manual replacement ofdischarged batteries in a robotic vehicle. Since the batteries typicallyweight in excess of 50 pounds, the manual effort to replace a battery isnot insignificant.

More fully automated systems are disclosed in U.S. Patent ApplicationPublication No. 2010/0181129, which describes a system for swappingbattery packs of an electric vehicle which includes an automatedconveyance system that pushes a replaceable battery into a batterycompartment on the vehicle. U.S. Pat. No. 9,776,326 describes a methodfor exchanging batteries at a battery exchange station which uses astationary robot to remove and replace exhausted batteries in a mobilerobot. Both systems are intended to relieve human workers from theburden of handling, e.g., lifting into place, the heavy batteries. Bothsystems, however, impose additional expense to purchase and maintain thebattery exchange robot.

Because of these limitations, it would be desirable to provide systemsand methods to reduce the power needs of such mobile robots, and thusprovide mobile robots having smaller batteries and/or extended servicetimes on a single battery charge, and methods and systems that mayreduce or eliminate the time required to recharge a mobile robot, suchas by providing improved systems and methods for battery exchange.

SUMMARY

The presently disclosed invention overcomes many of the shortcomings ofthe prior art by providing systems, devices and methods which reduce thepower needs of a mobile robot. Moreover, the presently disclosedinvention provides systems, devices and methods which reduce oreliminate the downtime required to recharge a mobile robot.

Accordingly, the present invention provides a field replaceable batterycomprising at least one battery cell, a main body configured to containtherein the at least one battery cell, means to enable movement of thefield replaceable battery, a charging interface for connecting the atleast one battery cell to an external power source, a blind mateconnector electrically connected to the at least one battery cell andconfigured to engage a corresponding blind mate connector on a batterypowered device, and a battery connection means angled with respect tothe longitudinal axis of the main body, wherein the angle is upward froma front end to a back end of the main body so that the field replaceablebattery is lifted into an engaged position on connection with thebattery powered device.

According to certain aspects of the field replaceable battery, thebattery connection means may be attached to left and right sides of themain body. The engaged position provides electrical connection betweenthe blind mate connector on the field replaceable battery and thecorresponding blind mate connector on the battery powered device.

According to certain aspects of the field replaceable battery, the meansto enable movement of the battery may be attached to a bottom of themain body, such as a bottom surface, and may include fixed and/orrotatable caters.

According to certain aspects of the field replaceable battery, thebattery connection means may be configured to engage complementarydevice connection means in a cavity of the battery powered device. Thedevice connection means may be positioned on an inner right side and aninner left side of the cavity. One of the device connection means or thebattery connection means may be a rail, and the other of the deviceconnection means or the battery connection means may be a set of wheelsconfigured to engage the rail.

According to certain aspects, the field replaceable battery may furtherinclude a locking handle having a locked position and an unlockedposition, wherein the locked position is configured to lock the fieldreplaceable battery in the engaged position on the battery powereddevice, and the unlocked position is configured to allowed movement ofthe field replaceable battery within the cavity of the battery powereddevice.

According to certain aspects, the field replaceable battery may furtherinclude a charge sensor configured to sense a charge state of the atleast one battery cell, and a circuit electrically connected to thecharge sensor for receiving a signal indicative of the charge state ofthe at least one battery cell.

According to certain aspects of the field replaceable battery, the mainbody may include a cover configured to provide access to an internalcompartment of the main body comprising the at least one battery cell,the charge sensor, and the circuit.

According to certain aspects of the field replaceable battery, theexternal power source may include a wired charging station, a wirelesscharging station, a direct connection to an AC power source, or acombination thereof. Accordingly, the charging interface may beconfigured to provide electrical connection with any of these externalpower sources.

The present invention further provides a power system for a mobile robotwhich includes the field replaceable battery according to any of theabove mentioned aspects, or combination of aspects, and a backup batteryconfigured to provide power to the mobile robot when the fieldreplaceable battery is removed or fully discharged.

According to certain aspects of the power system, the mobile robot mayinclude a mobile base comprising a cavity configured to accept the fieldreplaceable battery, at least one manipulator arm, a plurality ofsensors, a memory, and one or more robot processors coupled to theplurality of sensors, the memory, the mobile base, and the at least onemanipulator arm. The memory may comprise computer program instructionsexecutable by the one or more robot processors to process data receivedfrom each of the plurality of sensors, and output control signals to themobile base and the at least one manipulator arm.

According to certain aspects of the power system, the cavity of themobile base may include a device connection means configured to engagethe battery connection means. According to certain aspects of the powersystem, the cavity of the mobile base may include a device connectionmeans positioned on an inner right side of the cavity and configured toengage the battery connection means on the right side of the main bodyof the field replaceable battery, and a device connection meanspositioned on an inner left side of the cavity and configured to engagethe battery connection means on the left side of the main body of thefield replaceable battery.

According to certain aspects of the power system, the mobile robot mayfurther include a remote communication interface, and the memory maycomprise computer program instructions executable by the one or morerobot processors to receive data from and send data to a central server.

According to certain aspects of the power system, the field replaceablebattery may further comprise a charge sensor configured to sense acharge state of the at least one battery cell, and a circuitelectrically connected to the charge sensor for receiving a signalindicative of the charge state of the at least one battery cell. Thememory of the mobile robot may comprise computer program instructionsexecutable by the one or more robot processors to receive signal dataindicating the charge state of the at least one battery cell and alterthe navigation and/or work function based on the charge state of the atleast one battery cell. The memory of the mobile robot may comprisecomputer program instructions executable by the one or more robotprocessors to send data indicating the charge state of the at least onebattery cell to the central server and receive navigation instructionsfrom the central server.

The present invention further includes a lift counterbalance systemwhich includes a coil spring assembly comprising a tensioning springwithin an outer cylindrical cover, an inner polymeric cylinderpositioned either between the tensioning spring and outer cylindricalcover or on the inside of the tensioning spring, a cable accumulationcone operatively attached to an end of the tensioning spring, a cablehaving a first end attached to the cable accumulation cone and a secondend attached to a lift mechanism, and a pulley configured to guide thecable between the cable accumulation cone and the lift mechanism.Movement of the lift mechanism downward may pull the cable from thecable accumulation cone through the pulley and rotate the coil spring toincrease tension on the cable. Additionally, the inner polymericcylinder may dampen noise produced during rotation of the coil spring.

According to certain aspects of the lift counterbalance system, thesystem may further include a locking mechanism configured to retain thetension of the coil spring upon rotation thereof and in the event thecable breaks or is disconnected. Additionally, the system may furtherinclude a quick release mechanism to disconnect the lift mechanism fromthe cable.

According to certain aspects of the lift counterbalance system, thecable accumulation cone may be attached to an end of the tensioningspring, or an end of the outer cylindrical cover. The tensioning springmay be attached to an end of the cable accumulation cone or to an end ofthe outer cylindrical cover.

The present invention further provides a mobile robot comprising amobile base, at least one manipulator arm, a plurality of sensors, amemory, and one or more robot processors coupled to the plurality ofsensors, the memory, the mobile base, and the at least one manipulatorarm, wherein the memory comprises computer program instructionsexecutable by the one or more robot processors to process data receivedfrom each of the plurality of sensors, and output control signals to themobile base and the at least one manipulator arm.

According to certain aspects, the mobile robot may further include thefield replaceable battery according to any of the above mentionedaspects, or combination of aspects, and optionally a backup batteryconfigured to provide power to a mobile robot when the field replaceablebattery is removed or fully discharged. The field replaceable batterymay include a battery connection means attached to each of a left sideand a right side of the main body, each of the battery connection meansangled with respect to the longitudinal plane of the main body, whereinthe angle is upward from a front end to a back end of the main body sothat the field replaceable battery is lifted/elevated into an engagedposition on connection with the mobile base of the mobile robot, whereinthe engaged position provides electrical connection between the blindmate connector on the field replaceable battery and a correspondingblind mate connector on the mobile base.

According to certain aspects, the mobile base of the mobile robot, mayinclude a cavity configured to accept the field replaceable battery, andmay include a device connection means positioned on an inner right sideof the cavity and configured to engage the battery connection means onthe right side of the main body of the field replaceable battery; and adevice connection means positioned on an inner left side of the cavityand configured to engage the battery connection means on the left sideof the main body of the field replaceable battery. The device connectionmeans are angled upward from a front to a back of the cavity so thatengagement with the battery connection means on each of the left and theright side of the main body of the field replaceable battery lift thefield replaceable battery when pushed into the cavity and into theengaged position.

According to certain aspects, the at least one manipulator arm of themobile robot may include a first end portion pivotally carried by themobile base, a second end portion comprising an end effector, and anextension tool positioned at or near the second end portion andconfigured to provide access to an object without interference fromsurrounding objects or infrastructure within a logistics facility.

According to certain aspects, the mobile robot may include a verticalactuator stage configured to raise and lower relative to the mobilebase, the at least one manipulator arm having a first end portionmounted on the vertical actuator stage and a second end portioncomprising an end effector.

According to certain aspects, the memory of the mobile robot may includecomputer program instructions executable by one or more robot processorsto receive a signal or data from the circuit indicative of the chargestate of the at least one battery cell and alter a navigation path orwork task of the mobile robot based on the charge state, and/or may sendthe signal or data to the central server and receive an alterednavigation path or work task.

According to certain aspects, the mobile robot may include the liftcounterbalance system according to any of the above mentioned aspects,or combination of aspects. For example, the mobile robot may include aright lift counterbalance system and a left lift counterbalance system,wherein movement of the lift mechanism downward pulls the cable from thecable accumulation cone through the pulley and rotates the coil springto increase tension on the cable.

BRIEF DESCRIPTION OF DRAWINGS

Aspects, features, benefits and advantages of the embodiments hereinwill be apparent with regard to the following description, appendedclaims, and accompanying drawings. In the following figures, likenumerals represent like features in the various views. It is to be notedthat features and components in these drawings, illustrating the viewsof embodiments of the present invention, unless stated to be otherwise,are not necessarily drawn to scale. The illustrative embodiments in thefollowing drawings are not meant to be limiting; other embodiments maybe utilized and other changes may be made without departing from thespirit or scope of the subject matter presented herein.

FIGS. 1A and 1B are front and side views, respectively, of a mobilemanipulation robot in accordance with certain aspects of the presentlydisclosed invention.

FIG. 2 is a side perspective view of a mobile manipulation robot inaccordance with certain aspects of the presently disclosed invention.

FIGS. 3A and 3B are front and back perspective views, respectively, of amobile manipulation robot in accordance with certain aspects of thepresently disclosed invention.

FIGS. 4A and 4B are left and right side perspective views, respectively,of a field replaceable battery in accordance with certain aspects of thepresent invention.

FIG. 4C is a back view of the field replaceable battery shown in FIGS.4A and 4B.

FIGS. 5A and 5B are bottom and side perspective views, respectively, ofan internal cavity within a mobile base of a mobile manipulation robotin accordance with certain aspects of the present invention.

FIG. 6 is a front perspective view of an internal panel of a mobilemanipulation robot showing a counterbalance system in accordance withcertain aspects of the presently disclosed invention.

FIG. 7 is a block diagram of a robotic system with hardware and softwaremodules of a central server and a plurality of mobile manipulationrobots in accordance with certain aspects of the presently disclosedinvention.

FIG. 8 is a simplified overhead floor plan diagram of a representativelogistics facility.

FIG. 9A is a close-up view of a counterbalance system in accordance withcertain aspects of the present invention, and FIG. 9B is across-sectional view of a left uppermost region of FIG. 9A.

DETAILED DESCRIPTION

In the following description, the present invention involves systems andmethods for improved power supply and use in a battery powered devicesuch as a mobile manipulation robot. These systems include fieldreplaceable batteries that may be hot-swapped with no robot downtime,methods for automating battery replacement messaging and altering robotoperation when battery power is low, and improved mechanical systemshaving lower energy requirements, and thus extending the lifetime of thebattery operated mobile manipulation robot.

The above summary and drawings are not intended to describe or show eachillustrated embodiment or every possible implementation of the presentlydisclosed invention. Various aspects of the systems and methodsdisclosed herein may be described and illustrated with reference to oneor more exemplary implementations. As used herein, the term “exemplary”means “serving as an example, instance, or illustration,” and should notnecessarily be construed as preferred or advantageous over othervariations of the devices, systems, or methods disclosed herein.“Optional” or “optionally” means that the subsequently describedcomponent, event, or circumstance may or may not occur, and that thedescription includes instances where the event occurs and instanceswhere it does not. In addition, the word “comprising” as used hereinmeans “including, but not limited to”.

Various aspects of the systems disclosed herein may be illustrated bydescribing components that are coupled, attached, and/or joinedtogether. As used herein, the terms “coupled”, “attached”, and/or“joined” are interchangeably used to indicate either a direct connectionbetween two components or, where appropriate, an indirect connection toone another through intervening or intermediate components. In contrast,when a component is referred to as being “directly coupled”, “directlyattached”, and/or “directly joined” to another component, there are nointervening elements shown in said examples.

Relative terms such as “lower” or “bottom” and “upper” or “top” may beused herein to describe one element's relationship to another elementillustrated in the drawings. It will be understood that relative termsare intended to encompass different orientations of aspects of thesystems in addition to the orientation depicted in the drawings. By wayof example, if aspects of the mobile manipulation robot shown in thedrawings are turned over, elements described as being on the “bottom”side of the other elements would then be oriented on the “top” side ofthe other elements as shown in the relevant drawing. The term “bottom”can therefore encompass both an orientation of “bottom” and “top”depending on the particular orientation of the drawing.

It must also be noted that as used herein and in the appended claims,the singular forms “a”, “an”, and “the” include the plural referenceunless the context clearly dictates otherwise. Unless defined otherwise,all technical and scientific terms used herein have the same meanings ascommonly understood by one of ordinary skill in the art.

As defined herein, a Stock Keeping Unit (SKU) refers to a distinct item,and embodies attributes associated with the item that may distinguish itfrom another item. For a product, these attributes may include, but arenot limited to, the product manufacturer, product description, material,size, shape, color, weight, and packaging. Further, an individual SKUmay also have a code imprinted thereon which may indicate some of thesame above attributes. Examples of such codes include at least barcodessuch as a Universal Product Code (UPC), International Article Number(EAN), and Global Trade Item Number (GTIN).

The terms “goods” and “products” and “items” are used interchangeably,and may be taken to indicate items that need to be retrieved and/orstored. The terms “bin” and “tote” are also used interchangeably, andmay be taken to mean a container used to store products or goods whilethey are located on a shelf within a logistics facility, or as they aremoved throughout the logistics facility on a robotic system or conveyorbelt.

Referring now to the drawings, systems and methods according to thepresently disclosed invention are shown in FIGS. 1-9B. Like referencenumbers are used to label similar or shared components in each of thefigures (e.g., the mobile manipulator arm 120, 220, and 320, and themobile base 160, 260, 360 from each of the mobile manipulation robots100, 200, and 300, respectively). As such, reference to a componentdepicted in one figure, such as the mobile base 160 of FIG. 1A, may alsoinclude reference to the mobile base 260 in FIG. 2 and the mobile base360 in FIGS. 3A and 3B.

FIGS. 1A and 1B are front and side views of a mobile manipulation robot100 which may include a mobile base 160, a manipulator arm 120, aplurality of sensors (110, 150), and computer processors and memory (see718 and 716, respectively, of FIG. 7). The manipulator arm 120 may bemounted to the robot frame 125 at a position on top of the mobile base160 of the mobile manipulation robot 100. Alternatively, as shown inFIG. 2, the manipulator arm 220 may be mounted on a vertical stage 240which may be moveable vertically on the main body case 215 of the mobilemanipulation robot 200. A similar position for the manipulator arm 320is shown in FIGS. 3A and 3B, wherein the manipulator arm 320 is attachedto a distal end 342 of a vertical actuator stage 340, which is moveablevertically (i.e., up and down) with respect to a main body case 315 ofthe mobile manipulation robot 300. The vertical actuator stage 340 movesin tracks 380 positioned in the main body case 315.

In the various embodiments of the mobile manipulation robots shown inFIGS. 1A, 1B, 2, and 3B (100, 200, 300, respectively), a fieldreplaceable battery (190, 290, 390) may be inserted into a cavity withinthe mobile base (160, 260, 360). The computer processor and anyassociated components (memory storage, communication, connections) maybe positioned in a portion of the mobile manipulation robot protected byan enclosure, such as the mobile base (160, 260, 360) and/or the mainbody case (215, 315) of the mobile manipulation robot.

As shown in FIGS. 4A-4C, the field replaceable battery 400 may include amain body having a top side 410, left and right side walls (420A and420B, respectively), and front and back side walls (425 and 435,respectively).

The top side 410 may include a cover which may be opened to provideaccess to contents therein, such as at least one rechargeable batterycell. Exemplary rechargeable batteries include at least lithium ionbatteries, such as rechargeable lithium iron phosphate batteries (e.g.,55V, 110 Amp). Such batteries, which are configured to providesufficient power to the mobile manipulation robots disclosed herein, mayweight in excess of 50 pounds, such as at least 100 pounds. As such,they would generally be too heavy for the average person to lift and/ormaneuver. Thus, also provided on the main body may be a means to enablemovement of the field replaceable battery. For example, as shown in FIG.4B, wheels (440A, 440B) such as fixed or rotatable casters may beattached to a bottom of the main body of the field replaceable battery400. These may be included as sets of two or more wheels aligned toprovide movement while maintaining stability of the field replaceablebattery in an upright position (i.e., so that the battery does not tip).While wheels are shown in the figures, other means for movement of thefield replaceable battery are possible and are within the scope of thepresently disclosed invention. Moreover, while these wheels are shown tobe attached to a bottom surface of the field replaceable battery, suchmay be attached along sides of the field replaceable battery and mayextend below the bottom surface thereof to provide movement.

The main body may further include at least one connection means forengaging with complementary connection means on the battery powereddevice. For example, the main body may include at least one connectionmeans on each of the left and right side of the main body. Shown in FIG.4A is a connection rail 422A on the left side wall 420A of the mainbody. Shown in FIG. 4B is a connection rail 422B on the right side wall420B of the main body. Each connection rail is attached to the side ofthe main body at an angle 472 that deviates from the longitudinal axis470 of the main body. That is, the connection rails (420A, 420B) extendupward from a front side wall 425 to a back side wall 435 of the mainbody with respect to the longitudinal axis thereof.

The angle 472 may be at least 5°, such as at least 6°, or 7°, or 8°, or9°, or 10°, or 15°, or 20°, or 25°, or 30°, or 35°, or 40°, or 45°. Ingeneral, the angle would not exceed 45° as the force required to pushthe field replaceable battery into the cavity on the battery powereddevice is directly related to the angle 472. That is, the connectionrails provide a means to lift/elevate the field replaceable battery 400into an engaged position on the battery powered device.

The specific position of these connection rails on the sides of the mainbody provide a means to connect the field replaceable battery 400 with abattery powered device by engaging with complementary device connectionmeans in a cavity of the battery powered device. For example, the deviceconnection means may be positioned on an inner right side and an innerleft side of the cavity at a position complementary to the position ofthe battery connection rails (i.e., distance from the ground surface,angle, horizontal spacing, etc.).

As shown in FIG. 5A, the cavity of the battery powered device, such as acavity in the mobile base (160, 260, 360) of the mobile manipulationrobots (100, 200, 300), may include a left side wall 563, a closed backwall 566, a right side wall (not shown) and an open front. The fieldreplaceable battery 400 may be positioned (e.g., rolled on wheels 440A,440B) for connection by positioning the back side wall 435 of thebattery 400 proximate to the open front of the cavity in the batterypowered device. The connection rails (420A, 420B) may engage acomplementary connection means on each of the right and left side of thecavity.

For example, shown in FIG. 5A is a set of roller wheels 522A on the leftside wall 563 of the cavity, which are attached at an angle thatdeviates from the longitudinal axis of the side walls of the cavity bythe same amount, or by a similar amount, as the angle 472 by which therails on the field replaceable battery 400 deviated from thelongitudinal axis 470 of the main body thereof. That is, the connectionwheels on each side wall of the cavity extend upward from a front of thecavity toward a back wall 566 of the cavity with respect to thelongitudinal axis thereof. The connection means of the cavity may bepositioned along at least a portion of the inner cavity wall, such asalong a length on the inner cavity wall which is the same as, or similarto, the length of the rail on the side walls of the field replaceablebattery.

Connection of the field replaceable battery with the battery powereddevice is as simple as positioning the back side 435 of the battery 400proximate the open front side of the cavity, and pushing the batteryinto the cavity. The connection means on the outer side walls of themain body of the battery will engage with the connection means on theinner side walls of the cavity so that when the field replaceablebattery is pushed into the cavity of the battery powered device, thebattery is lifted into the cavity with a bottom of the battery suspendedabove the ground surface (e.g., floor). In this way, the wheels (440A,440B) of the field replaceable battery are lifted/elevated off of theground surface.

While the connection means on the main body of the field replaceablebattery are shown to be rails, and the connection means on the innerside walls of the cavity in the battery powered device are shown to beroller wheels, other arrangements are envisioned and within the scope ofthe present application. For example, the connection means on the mainbody of the field replaceable battery may be roller wheels, and theconnection means on the inner side walls of the cavity in the batterypowered device may be rails. Moreover, interlocking rails or othercomplementary connection means may be included on both the fieldreplaceable battery and the cavity. Additionally, while the cavity isdefined as having side and back walls, any means to secure theconnection means is within the scope of the present invention, such asadditional rails or structural features.

Either or both of the field replaceable battery and the cavity of thebattery powered device may include additional alignment means which mayassist in positioning the field replaceable battery during connectionwith the cavity. For example, as shown in FIGS. 5A and 5B, the alignmentmeans may include protrusions or rails 532 on the inner side walls ofthe cavity which may laterally position the field replaceable battery400 within the cavity. While the alignment means are shown as rails onthe inner side walls of the cavity, they may alternatively, oradditionally, be positioned on the side walls of the main body of thebattery powered device. Moreover, while the alignment means are shown asrails, they could also be projections, wheels, etc.

For reference, FIGS. 5A and 5B also label bottom and top walls of thebattery powered device (562 and 564, respectively), and an outer sidewall of the battery powered device 567. The battery powered device maybe part of a mobile manipulation robot, and as such, the region depictedin FIGS. 5A and 5B may be an internal structural portion of the mobilebase of the mobile manipulation robot, such as those depicted in FIGS.1A, 1B, 2, 3A, and 3B (100, 200, 300). As such, various other componentsmay be included in the region surrounding the cavity, such as wheels 565(e.g., wheels 165 of FIGS. 1A and 1B), shocks 542, and additionalbatteries 575.

Once the field replaceable battery 400 is fully inserted (pushed) intothe cavity of the battery powered device, an electrical connection maybe established between the two via a connector. A preferred connectorincludes a blind mate connector the field replaceable battery which maybe configured to make an electrical connection with a blind mateconnector on the battery powered device. Shown in FIG. 4B is a blindmate connector 450 on a back side of the front wall 425 of the main bodyof the field replaceable battery 400. This blind mate connector isconfigured to engage a corresponding blind mate connector 550 on thebattery powered device (see FIG. 5A and 5B) to electrically connect theat least one battery cell of the field replaceable battery 400 to powersupply circuitry of the battery powered device (e.g., the mobilemanipulation robot) when the field replaceable battery 400 is installedin the cavity.

While the blind mate connector on the field replaceable battery and thebattery powered device are shown in one specific position on each, suchas toward a front of the field replaceable battery and the cavity of thebattery powered device, other positions are possible and within thescope of the present invention. For example, the blind mate connectorsmay also be positioned toward a back of the cavity and on a back wall ofthe field replaceable battery, or may be position on a top of the fieldreplaceable battery and on a upper surface of the cavity of the batterypowered device.

The field replaceable battery 400 may further include a locking handle430 having a locked position and an unlocked position. For example, thelocked position may be configured to lock the field replaceable battery400 in an engaged position on the battery powered device. In the engagedposition, the field replaceable battery 400 is fully pushed into thecavity of the battery powered device and the blind mate connectors oneach (450 and 550, respectively) are connected to provide electricalconnection between the field replaceable battery 400 and the batterypowered device. The unlocked position of the handle may be configured toallowed movement of the field replaceable battery 400 within the cavityof the battery powered device (e.g., insert or remove the battery fromthe cavity on the battery powered device). The locked position may be aposition of the handle which is rotated with respect to the unlockedposition, such as by 90 degrees or even 180 degrees, or a position whichis pulled out or pushed in with respect to the respect to the unlockedposition, or any combination thereof.

As indicated above, the field replaceable battery 400 includes at leastone rechargeable battery cell. Further, the field replaceable battery400 may include a charge sensor configured to sense a charge state ofthe at least one battery cell, and a circuit electrically connected tothe charge sensor for receiving a signal indicative of the charge stateof the at least one battery cell. Additional sensors may be includedwhich register a temperature, voltage, current, etc. of the at least onebattery, and such information (data) may also be relayed via a circuit.Additionally, when more than one battery cell is included in the fieldreplaceable battery, each individual battery may include a charge sensor(and optionally additional sensors), which may communication viaindividual circuits, or may communicate directly, to a batterymanagement system. Such a system manages a rechargeable battery (cell orgroup of cells), such as by protecting the battery from operatingoutside its safe operating area, temperature, voltage, etc.; and bymonitoring its state, calculating secondary data, reporting that data,controlling its environment, authenticating it and or balancing theusage of individual cells in a groups of cells.

The cover 410 on the main body of the field replaceable battery 400 maybe configured to provide access to an internal compartment of the mainbody comprising the at least one battery cell, the charge sensor andcircuit, and any other additional relays or circuitry contained therein(e.g., relays, communication wiring, electrical connection wiring,charging management PCA, etc.). The cover 410 may be hinged; may snaponto top edges of the front, back, and/or side walls; may screw into topportions of the front, back, and/or side walls; or any combinationthereof.

The field replaceable battery 400 further includes a connection meansfor an external power source which may provide for recharging of the atleast one battery cell. For example, the external power source may beprovided by AC power from a wall outlet, and the connection means mayinclude a standard power cord. Alternatively, the external power sourcemay be provided by a battery docking station which acquires power from astandard wall outlet. The battery docking station may provide power tothe field replaceable battery via direct contact between one or moreelectrical charging contacts. The battery docking station may providepower to the field replaceable battery wirelessly. Moreover, more thanone means for recharging may be included on the field replaceablebattery 400.

According to certain aspects of the present invention, the fieldreplaceable battery may be part of a power management system that mayalso include a backup battery to provide power to the battery powereddevice when the field replaceable battery is removed or fullydischarged. Moreover, the power management system may include thebattery docking station or AC plug as described hereinabove. The fieldreplaceable battery may indicate a charge status on a visible face ofthe main body either through one or more lights or a visible readout.Alternatively, or additionally, the field replaceable battery mayindicate the charge status by an audible signal that may change (e.g.,start at a certain charge state, grow louder and/or increase frequencyof signal, etc.) as the battery is progressively discharged.

According to certain aspects of the present invention, the batterypowered device may be a mobile manipulation robot. As such, the presentinvention further provides a power system for a mobile manipulationrobot which includes the field replaceable battery describedhereinabove, and a backup battery configured to provide power to themobile manipulation robot when the field replaceable battery is removedor fully discharged (see for example reference number 575 in FIG. 5B).

Power management in mobile robotic applications can be critical tooptimal system performance. As such, the power status of the fieldreplaceable battery may be monitored via a battery management systempower control assembly (PCA). Recharging of a depleted battery may bemonitored for efficient and complete charging. Moreover, the modularityof the field replaceable battery enables the rapid removal andinstallation of a charged field replaceable battery. In addition, theinternal guide rails/slides assist by providing a lifting, elevatingmotion to the field replaceable battery as it is inserted/plugged intothe mobile manipulation robot connector. The field replaceable batteryslides into the mobile manipulation robot with a slow, steady motion andis gently lifted into the cavity in the mobile base until the blind mateconnection is made at the end of the insertion motion. The designprovides for insertion guidance in all the degrees of freedom thataffect the insertion motion.

The further inclusion of a battery backup system (575 of FIG. 5B) allowsthe mobile manipulation robot to remain powered on and running duringremoval of a depleted battery and insertion of a fully charged battery.This battery backup system provides a productivity and uptime benefit tothe user as the software restart time is eliminated since the systemsoftware status is maintained and functioning during the fieldreplaceable battery replacement procedure.

Exemplary mobile manipulation robots may include those depicted in FIGS.1A, 1B, 2, 3A, and 3B, which may use advanced communication systems asshown in FIG. 7 to perform in a specific environment, such as thelogistics facility depicted in FIG. 8.

FIGS. 1A and 1B are front and side views of a mobile manipulation robot100 according to certain aspects of the present invention. Internaldetails of software components of the mobile manipulation robot andsoftware relevant to a system which includes at least one mobilemanipulation robot are shown in FIG. 7, which provides a block diagramof a system comprising a central server 700 and at least one mobilemanipulation robot (100, 200, 300). The server may have an electroniccommunications interface (server communication interface 740) thatconnects with an electronics communication interface on the mobilemanipulation robot(s) (remote communication interface 710). Thisconnection may be established through a wireless network via a wirelessaccess point. Various other types of communication are possible and maybe used in addition to, or as an alternative to wireless communication,such as a tethered wire connection or other point-to-point wireless dataexchange.

With specific reference to FIGS. 1A and 1B, and FIG. 7, the mobilemanipulation robot 100 may have a wheeled mobile base 160, an internallypositioned battery 190 such as the field replaceable battery 400, and anonboard computer processor 718 with memory storage 716. The mobilemanipulation robot may also have at least one temporary storage bed 140for picked items and at least one robotic manipulator arm 120. Theonboard computer processor 718 may be configured to run a set ofprograms with algorithms capable of performing navigation and picking.Further, the onboard computer processor 718 utilizes data from sensors(150, 110) to output control signals to the mobile base 160 andmanipulator arm 120 for navigation and picking, respectively.

Moreover, the onboard computer processor 718 may be configured to run aset of programs with algorithms capable of receiving signal data fromthe charge sensor and/or a circuit connected to the charge sensor, bothassociated with the at least one battery cell of the field replaceablebattery 400. The signal data may indicate a charge state of an engagedfield replaceable battery 400 (i.e., battery engaged in the cavity ofthe mobile base). The onboard computer processor 718 may be configuredto run one or more programs which would alter a navigation path of themobile manipulation robot when the charge state of the battery cells inthe field replaceable battery is low, or below a set threshold point.Alternatively, or in addition, the onboard computer processor 718 may beconfigured to run one or more programs which would communicate thecharge state of the at least one battery cell in the field replaceablebattery to a central server 700, and receive navigation and/or pickinstructions from the central server based on the charge state of the atleast one battery cell.

The onboard computer processor 718 may also have local persistent memorystorage 716 which stores specific information relevant to theconfiguration of each manipulation robot (100, 200, 300). Suchinformation may include sensor calibration data, battery usage data(e.g., rate of use for specific activity loads, etc.), actuator tuningparameters, and other platform specific data. The onboard computerprocessor 718 may also communicate with the central server 700 toreceive pick order information and respond back with confirmation datato inform the central server 700 of successful picks or any errors thatmight occur.

Each manipulation robot (100, 200, 300) may also have a user interface(130, 230, 330) which includes a graphical display monitor and an inputdevice, where the input device may be a touch screen, a track ball,voice command, a keyboard, input buttons or any combination of thesedevices and possibly others. The user interface (130, 230, 330) allows auser to command and control each mobile manipulation robot to performlocalized tasks and to enter product picking dispatch informationmanually, thus sending the robot on its mission. For example, a statusof the field replaceable battery may be displayed on the graphicaldisplay monitor, and a user may interact with the mobile manipulationrobot through the graphical display monitor to change the navigationinstructions based on that status.

Additionally, according to the presently disclosed invention, eachmobile manipulation robot may contain an external swappable memory porton a side, where necessary information may be uploaded to the robotdirectly when the operator inserts a data storage device, thusby-passing the wireless communication to the server. The data storagedevice may be a disk, USB flash device, or other form of external memorystorage device. The data may also be transferred through proximitycommunication technologies, such as near field communication (NFC),Bluetooth, or short-range radio-frequency identification (RFID)standards.

Each manipulation robot (100, 200, 300) may also be equipped with safetyfeatures which can include: one or more safety lights or strobes (155,255, 355), an audible warning annunciator or horn, one or more emergencystop buttons 157, the ability to display fault, error, battery chargestatus, and/or intended action (such as navigation turn signal)information on the user interface (130, 230, 330) or at some other pointon the manipulation robot, or any combination thereof.

Furthermore, each manipulation robot 100 may be configured to receivesignals from the central server 700, or directly from the warehousemanagement system (WMS) 701, which may indicate an emergency and maydirect the mobile manipulation robot (100, 200, 300) to stop and/or mayfurther activate the one or more safety lights or strobes (155, 255,355) and/or audible warning annunciator or horn. In the event that anunstable and/or unsafe diagnostic state for the mobile manipulationrobot (100, 200, 300) is detected by the one or more robot processors718, the mobile manipulation robot may be stopped. The mobilemanipulation robot (100, 200, 300) may also be stopped if the sensors(150, 110 and 350, 310) detect a human or obstacle in close proximity,or detect unsafe operation of the mobile manipulation robot. Suchsignals may be processed by the robot processors 718 and/or at thecentral server 700 to control the robot speed and or direction ofoperation.

The mobile manipulation robots disclosed herein may use an articulatedrobot manipulator arm (120, 220, 320) to pick pieces with the commonvariability found in item size, shape, weight and placement within alogistics facility. Common logistics storage infrastructure, such as anordinary shelf or rack, does not constrain any item location andorientation for the purposes of any deliberate accuracy, therefore, inorder for a robot to do a pick at random it must have sufficient freedomto grasp an item in various configurations. As such, a highdegree-of-freedom robot manipulator arm (120, 220, 320) may be used toprovide the manipulability necessary to pick an item in anyconfiguration in which it is found.

With continued reference to FIGS. 1A, 1B, 2, 3A, and 3B, the mobilemanipulation robot (100, 200, 300) may physically adjust for variationsin item location and orientation which may be determined from sensor(110, 310) information prior to the pick. The manipulator arm 120 may bemounted to the robot frame 125 at a position on top of the mobile base160 of the manipulation robot 100. The manipulator arm 120 enables therobot to reach multiple shelf level heights.

The vertical reach of a robot may be extended, for example, by mountingthe manipulator arm 120 on a vertical actuator stage, such as shown inFIGS. 2, 3A, and 3B, wherein the manipulator arm is mounted on a distalend 342 of the vertical actuator stage which includes the storage bed orplatform 356 that may hold pieces or totes (145, 245). The verticalactuator stage (240, 340) would be able to raise and lower themanipulator arm (220, 320) so an end effector (275, 375) can reach bothhigher and lower pick locations.

Providing lift to the vertical actuator stage having the mobilemanipulator arm attached at a distal end thereof may require significantpower. Even in the empty state (i.e., empty of items or totes), thevertical actuator stage and the mobile manipulator arm may representsignificant weight. In an effort to reduce the power required to movethe vertical actuator stage, the mobile manipulator robot may include aunique lift counterbalance system.

The design and application of the lift counterbalance system isgenerally for the purpose of conservation of energy, and to create anassist mechanism to aid the mobile manipulator robot to raise thevertical actuator stage and loads thereon for the proper function of thesystem. The disclosed dual spring system generally includes thefollowing system elements: 1) spring support/structure tubes forconnecting and supporting the spring components, 2) springs that providethe energy storage medium and reside inside the support/structure tubes,3) two tapered cable accumulation cones that provide a variable loadingfeature to the springs, 4) cables for connecting the vertical actuatorstage to the counterbalance spring system, 5) inner polymeric tubes thatextend a portion of or the entire length of the support tubes and fit inbetween the support tubes and springs, providing an insulation barrierand sound damping feature to the system, and 6) two pulleys which guidethe cables to the robot lift mechanism. The system may further include7) a dual locking, spring retention system that is configured to retainthe spring load as it builds from the rotation of the spring tubes andsprings, such as a ratcheting, spur and latch, in addition to providingan anti-rotation/retention feature should the wire cables fail, 8) aquick release clevis pin attachment-detachment device included for easeof assembly and service of the mobile lift counterbalance system, and 9)a manual spring tensioning (see 631 of FIG. 9B, manually tensioning toolattachment point) capability provided by a tool connection point/part onthe end of each spring end.

As shown in FIG. 3A, a mobile manipulator arm 320 may be attached on adistal end 342 of the vertical actuator stage 340, which may be attachedto a main body case 315 of the mobile manipulation robot 300 in verticaltracks 380. A centering or alignment track 354 may also be included onthe main body case 315 which may further stabilize and/or align thevertical actuator stage 340 during movement (i.e., raising or loweringrelative to the main body case 315). Furthermore, a back plate 352 maybe included on the vertical actuator stage 340 which may protect objectsor totes placed thereon.

The mobile manipulation robot 300 may include the counterbalance system600 on an inside of the main body case 315. With reference to FIGS. 6,9A, and 9B, the lift counterbalance system 600 generally includes a coilspring assembly (610A, 610B) comprising a tensioning spring 626, anouter cylinder cover 628, and an inner polymeric cylinder 624. Thetensioning spring may be attached via an end thereof to the outercylinder, and via an opposite end to a fixed point on the mobilemanipulation robot, such as to a panel (see 632 of FIG. 6), so thatrotation of the cylinder may generate tension on the spring. The innerpolymeric cover 624 may be positioned between the outer cylinder cover628 and the tensioning spring 626, or may be positioned on the inside ofthe tensioning spring (see FIG. 9B).

Alternatively, the tensioning spring may be attached via an end thereofto a tapered cable accumulation cone, and via an opposite end to a fixedpoint on the mobile manipulation robot, such as to the panel 632, suchthat rotation of the cone may generate tension on the spring. The innerpolymeric cylinder 624 may be positioned between the outer cylindercover 628 and the tensioning spring 626, or may be positioned on theinside of the tensioning spring (see FIG. 9B).

Alternatively, a winding shaft may be positioned within the tensioningspring and attached to an end of the tensioning spring, the other end ofthe tensioning spring fixed a point on the mobile manipulation robot asindicated above, such that rotation of the winding shaft may generatetension on the spring. The outer cylinder may cover the tensioningspring, and the inner polymeric cylinder may be positioned between thetensioning spring and the winding shaft. In this case, the tensioningspring may be attached via an end to the winding shaft, and rotation ofthe winding shaft may generate tension on the tensioning spring.

A unique feature of the lift counterbalance system 600 disclosed hereinis the inclusion of the inner polymeric cylinder, which may reducevibration of the tensioning spring and thus may dampen noise generatedwhen the tensioning spring is rotated (e.g., by the outer cylinder,cable accumulation cone, or winding shaft).

The presently disclosed counterbalance system further comprises a cableaccumulation cone operatively attached proximate an end of the coilspring assembly (610A, 610B). A cable 614 may have a first end attachedto the cable accumulation cone and a second end attached to a liftmechanism 622, such as a lift mechanism attachable to, or part of, thevertical actuator stage 340 of the mobile manipulation robots disclosedherein. For example, and with reference to FIG. 3A, when the liftcounterbalance system is housed within the main body case 315 of themobile manipulation robot 300, a portion of the lift mechanism 622 mayextend through the vertical tracks 380 of the main body case 315 andattach to the vertical actuator stage 340.

The lift counterbalance system may further include a pulley 612configured to guide the cable 614 between the cable accumulation coneand the lift mechanism 622. Movement of the lift mechanism 622 downwardmay pull the cable 614 from the cable accumulation cone through thepulley 612 and rotate the coil spring to increase tension on the cable614. The cable accumulation cone may be tapered to provide a variableload to the tensioning spring. As such, downward movement of thevertical actuator stage may generate an even tension on the spring andthus an even load on a motor used to provide the movement to thevertical actuator stage. Moreover, the lift counterbalance system actsto reduce the overall load on this motor, such that a much smaller,lighter weight, lower power motor may be enabled to provide movement tothe vertical actuator stage. This lessens the power load on the batteryused to power the mobile manipulation robot (e.g., the field replaceablebattery detailed herein).

Additionally, the inner polymeric cylinder may dampen noise producedduring rotation of the coil spring.

The lift counterbalance system may further include a locking mechanism618 configured to retain a tension of the coil spring upon rotationthereof and in the event the cable 614 breaks or is disconnected.Exemplary locking mechanisms include a ratcheting, spur and latchsystems.

The lift counterbalance system may further include a quick releasemechanism 620, such as a clevis pin, to disconnect the lift mechanism622 from the cable 614. According to certain aspects of the liftcounterbalance system, the cable accumulation cone may be attached to anend of the tensioning spring, or may be attached to an end of thewinding shaft.

The lift counterbalance system 600 may be attached to an internalvertical panel 632 having a top end 630A and a bottom end 630B. Thepulleys 612 may be position near a top end 630A of the panel 632 so thatas the lift mechanism 622 moves downward, the cable 614 pulls away froma top of the coil spring assembly (610A, 610B) and rotates thetensioning spring therein. This rotation increases a tension of thetensioning spring, acting to counterbalance the load of the verticalactuator stage 340. As shown in FIG. 6, the mobile manipulation robotmay include two coil spring assemblies, wherein a cable from a leftassembly 610A may connect to a right lift mechanism 622 via a pulley onthe right, and a cable from a right assembly 610B may connect to a leftlist mechanism (e.g., in a crisscross fashion). Each of the left andright list mechanisms will act on the left and right sides of thevertical actuator stage, respectively, to counterbalance the load on thestage.

The vertical actuator stage (240, 340) may comprise a conveyance meanssuch as rollers, which may improve movement of a tote 245 onto or off ofthe stage (platform). Alternatively, the vertical actuator stage (240,340) may comprise a mechanically actuated conveyance device that allowsfor automatic transfer. The conveyance device may be a small conveyorbelt or may be a set of rollers or wheels which is capable of shiftingthe tote 245 to and from another platform or conveyance (see 820 of FIG.8, or a retrieval queue of a pack and ship area 850, or a retrievalqueue of a replenishment area).

Additional high degree-of-freedom robot manipulator arms (120, 220, 320)may be included which may provide additional lift capability to pickobjects of various shapes and sizes when the arms work cooperatively, orto pick more than one object at a given pick location using arms workingin parallel but independently. For multi-arm robots, the arms may be thesame or may have different kinematic configurations, and may have thesame or may have different end effectors.

The mobile manipulation robot (100, 200, 300) may use a grasping endeffector (175, 275, 375) on the manipulator arm (120, 220, 320) to pickitems from their stored location and transfer them to a temporarylocation, or vice-versa. The grasping end effector may be a suction cup,which may be connected to a vacuum pump through an onboard computerprocessor 718 controlled valve. The vacuum suction at the suction cupmay be engaged and disengaged by actuating the valve, thereby allowingthe manipulation robot to grasp the desired pick item on contact andthen release it when necessary. The use of a suction cup also allows therobot to grasp a target piece at a single point and orientation, whichreduces the computation time required for the system to determine how tograsp the pick item.

Alternatively, the end effector may be a mechanically actuated grippersuch as, for example, a robotic hand having articulated digits. The endeffector may be a simple gripper, an electroadhesion end effector, amagnetic end effector, or combinations thereof, and the robots maycomprise an end effector swap mechanism configured to permit a change ofthe end effector. Exemplary magnetic end effectors may utilizeelectromagnets, permanent magnets, or magnet arrays which provideopposing magnetic fields. An electroadhesive end effector may usereversible electrostatic adhesion to grip an item while it is picked andput. When an electroadhesive or magnetic end effector is used, such maybe powered by an electrical power supply configured to generate anelectrostatic or magnetic adhesive force that is used to releasablyadhere the item to the end effector. The onboard computer processor 718(see FIG. 7) may control the power supply to activate and deactivate theelectrostatic or magnetic adhesive force of the end effector.

The decision to use of one, various interchanged, or a combination ofend effector technologies is driven by the physical properties of theobjects to be grasped so that a sufficient amount of lift force isgenerated to carry the objects by the manipulator aim without causingdamage or visible alterations to the objects.

The presently disclosed system design may also include an extension tool(170, 270, 370) mounted at the end of the robot manipulator arm (120,220, 320), as shown in FIGS. 1A, 1B, 2, 3A, and 3B. This tool (170, 270,370) may enable the manipulation robot (100, 200, 300) to position thegrasping end effector (175, 275, 375) at a sufficient depth into astorage rack so that the end effector may reach a desired item whilemaintaining clearance for the manipulator arm (120, 220, 320; i.e., sothat the manipulator arm does not come into contact with theinfrastructure). It may also enable the end effector (175, 275, 375) toreach into shelf corners where it would otherwise not have clearance forthe robot manipulator arm (120, 220, 320).

Accordingly, the extension tool (170, 270, 370) may be sized based onspecifics of the logistics facility such as, for example, shelf depth.That is, the extension tool may be long enough to reach into the back ofa shelf, as mentioned above, so that the end effector may pick a pieceplaced therein. Furthermore, the extension tool may have a diameter thatis smaller than the diameter of the end effector. This may allow theextension tool to reach into a shelf without obstructing the view of theend effector and/or the piece to be picked, and may simplify thecomputation required to locate the piece as no additional sensorinformation may be required to locate the extension tool; informationregarding the end effector would be sufficient.

The extension tool (170, 270, 370) may be a replaceable or switchablepart of the robot manipulator arm (120, 220, 320). In this way,logistics facilities having different configurations such as, forexample, deeper shelving, may be accommodated by simply switching outthe extension tool to one more suited for the work (e.g. a longerextension tool). Furthermore, in cases where an end effector (175, 275,375) may require a different connection mechanism, the use of variousextension tools having different connection mechanisms at the end usedfor connection to the end effector, may streamline switching an endeffector on the robot manipulator arm. That is, the ability to switchout the extension tool to one having a suitable connection means for thedesired end effector may improve the ease of use of the mobilemanipulation robot (100, 200, 300).

After pieces are picked, they may be placed into the storage bed (140,240, 340) for transportation. The bed may also carry a container (145,245), such as a box or tote, in which the items can be placed. Thismethod enables multiple items to be picked for a given order or batch oforders. This method frees the robot manipulator arm (120, 220, 320) topick additional pieces without needing to take multiple trips to andfrom an order transfer area (see 860 of FIG. 8). Additionally, bycarrying a packing box or container or transport tote onboard, themobile manipulation robot (100, 200, 300) is able to aggregate orderpieces together into a single container that can be easily swapped witha different container for additional order fulfillment.

The mobile manipulation robots may further include at least one sensor(110, 310) which may be positioned on the at least one mobilemanipulator arm (120, 220, 320) such that rotation of the arm directsthe at least one sensor toward the product to be picked foridentification and localization. For example, the at least one sensor(110, 310) may be positioned on a central point of the mobilemanipulator arm (see sensors 110 of arm 120 in FIG. 1A), or at a point354 along the extension tool 370 (see FIG. 3A).

Positioned opposite the at least one sensor (110, 310) may be at leastone opposite sensor that may be mounted such that once the mobilemanipulator arm (120, 220, 320) angles itself to pick the product, theopposite sensor is now aimed directly into the storage bed (140, 240,340) or transport tote (145, 245) where the product is to be placed.This opposite sensor may provide the data necessary to allow the onboardcomputer processor 718 (see FIG. 7) to analyze the storage bed ortransport tote to find the optimal location to place the product, or anadditional tote, considering that there might be previous objectsalready container thereon, or additional totes already containedthereon. Additionally, with two such sensors (110, 310) aimed inopposite directions, the system may be able to pick from the left or theright side of the mobile manipulation robot based on product location.

The storage bed (140, 240, 340) may comprise a calibration target whichmay be viewed by one or more of the sensors (110, 310) placed on themobile manipulator arm (120, 220, 320). These centrally located sensorsmay be positioned to view the calibration target on the storage bed whenthe mobile manipulator arm is rotated. As such, information on thecalibration target may be used to calibrate these sensors to ensure thatall parameters are within specifications, and if not, update theparameters to reflect the current configuration. The dual use of thestorage bed (140, 240, 340)—as a platform to hold picked items and as acalibration target—reduces the size profile of the presently disclosedmanipulation robot and improves the accuracy of the system.

The location of one or more sensors (110, 310) on the mobile manipulatorarm (120, 220, 320) may provide improved piece-picking accuracy. First,these sensors will have an unobstructed and enlarged view of the itemsto be picked and their storage locations, which is improved over theview that is provided by sensors placed at the end of a robotic arm oron the mobile base, as is the case in many prior art systems.Furthermore, sensors mounted at the end of a robotic arm may get in theway of, or reduce the range of positions available to, an end effector;sensors mounted on the mobile base may have their view of the items tobe picked and their storage locations impeded by movement of the roboticarm.

Second, the location of the one or more sensors (110, 310) on the mobilemanipulator arm (120, 220, 320) may provide improved measurementaccuracy of the item to be picked. The mobile manipulator arm may moveand articulate at more than one point along the arm, and each movementintroduces potential error to any measurements that may be made betweenthe end effector (175, 275, 375) and the items to be picked by sensorspositioned on the mobile base (160, 260, 360). Placement of the sensorson the mobile manipulator arm may reduce this error by bringing thesensors closer to the items to be picked, and thus removing the errorinherent in several points of articulation.

FIG. 8 shows an exemplary top view floor plan of a section of alogistics facility 800. The mobile manipulation robots may be includedan a system and method which enables objects to be picked within adefined robot work zone 830 wherein stocked objects are stored on commoncommodity shelving 810. The system and method may define a plurality oftransfer areas 860 in which items would be transferred to and from themobile manipulator robot(s) 100 (and 200, 300 from FIGS. 2, and 3A and3B, respectively). The transfer area 860 may possibly interface with apacking and shipping station 850, or a conveyor 820, or a staging area,or any combination thereof.

At the transfer area 860, a worker may remove the picked items orcontainer (145, 245) holding the items from the mobile manipulationrobot. If a container (145, 245) is removed, a new container could betransferred to the robot for fulfillment of the next order. The methodmay employ transfer of picked items or the container by a human operatoror, the transfer of items may be automatic. That is, the onboard robotstorage bed (140, 240, 340) may have a mechanically actuated conveyancedevice that allows for automatic transfer. The conveyance device may bea small conveyor belt or may be a set of rollers or wheels, which iscapable of shifting the held pieces or container to and from anotherplatform or conveyance.

Alternatively, the automatic transfer of objects from the onboardstorage bed (140, 240, 340) may be performed by the manipulator arm(120, 220, 320) of the manipulation robot (100, 200, 300). Themanipulation robot may transfer individual pieces by using its endeffector (175, 275, 375) grasping mechanism or the robot may transfer acontainer carried in the storage bed by manipulating it with anextension tool (170, 270, 370) and end effector tool (175, 275, 375).The system may be designed to interface automatically with a separateconveyor system 820 which may be adjacent to the transfer area 860,whereby pieces or containers could be automatically moved through aconveyor 820 around a facility to and from a robot picking area 830.This method has the advantage of requiring less manual work to be doneto transfer objects from a manipulator robot 100 after they are picked.

With reference to FIG. 7, the system's central server 700 may be used toprocess order information that is transacted with a WMS 701, and maycoordinate the fulfillment of orders with a plurality of manipulationrobots 100. All computation on the server 700 may be executed by one ormore internal processors 720. The server may have two software modulesthat enable this order fulfillment coordination. The first processor maybe a task dispatch module 728, which analyzes orders received from a WMS701, and determines which of the plurality of manipulation robots 100 isto be assigned to an order. After a mobile manipulation robot isselected for picking an order, the task dispatcher 728 instructs themobile manipulation robot with high-level order picking information,such as, route navigation paths, SKU locations, and an order drop-offlocation. The task dispatcher 728 works closely with a system statemonitor 730 to obtain key feedback information from the system. Thesystem state monitor 730 may communicate with the mobile manipulationrobots to keep track of their current physical location within thefacility, along with status information, which may include but is notlimited to: whether the mobile manipulation robot is currently assignedan order, any faults or error modes, health information, such asremaining battery power, or charging status.

The central server 700 may also be used to store and process centralizedSKU information in an SKU database 756, which stores informationrequired by the robots to complete the order picking. The processing ofthis SKU specific information may be executed within a SKU analysissoftware module 726. The SKU information can include SKU size and shapedata, which can include physical dimensions, 3D geometry that caninclude point and triangle mesh structures, item weight, appearanceinformation that can include colorized texture maps, and may include SKUmarking codes, that can include barcode and UPC data. Additionally, thecentral server 700 may store information in the SKU database 756 aboutthe locations and regions on the surface of the individual SKU unitsthat are allowed, or not allowed, for grasping by the mobilemanipulation robot 100. This allows the manipulation robot 100 to graspan item in a way that is known to be safe and stable, and prevents therobot from grasping an item at a point or in a way that is unsafe orunstable.

With continued reference to FIGS. 1A, 1B and 7, the onboard robotstorage bed 140 may be configured to sense the weight of the pieceplaced thereon. This information may be communicated to the centralserver 700, and may provide additional verification that the correct SKUwas picked, and that the item was properly transferred to the onboardrobot storage bed 140. If the wrong weight is sensed in the storage bed140, the manipulator arm 120 may be used to remove the item from thestorage bed. The item may be replaced to the storage location by themanipulator arm 120, or a signal may be sent to the central server 700requesting manual assistance, such as from a human pick worker. In theevent that no weight is sensed in the storage bed 140, the manipulatorarm 120 may be used to select another replacement item and/or retrievethe dropped item. Further, a signal may be sent to the central server700 requesting manual assistance, such as from a human pick worker, orto alert the system to a change in the SKU inventory.

The central server 700 may also store information about the state of theSKU inventory in the SKU database 756, and may process this informationin the SKU analysis module 726. Such information may include theposition of items in their stored location, the location and orientationof grasping points for the robot to attempt to pick, and the sequence inwhich items of the same SKU type and approximate location should bepicked from the shelf. This enables a sufficiently fast pickingoperation for the manipulation robot 100, such that picking geometry andsequencing can be planned and stored in memory 756 on the central server700 or, and also, on the local storage 716, and does not need to becomputed at the time of pick by a given manipulation robot 100. Thecentral server 700 enables multiple manipulation robots 100 to shareinformation about the state of inventory and plans for picking, so thatdifferent robots 100 can pick from the same storage location, withouteach one needing to sense and compute pick information.

Additionally, the central server 700 may store information about theinfrastructure of the facility of operation in a map storage database754. This can include information about the storage racks 310 such asshelving dimensions (width, depth and height), separate shelf levelheights, shelf face widths, and rack column widths. The infrastructureinformation can be created, modified and analyzed through a map creationsoftware module 724 on the central server 700. Using this module, ahuman operator can manually create a facility map or may load the mapdata from a predefined file, such as a Computer Aided Drawing (CAD)file, or may load mapping data automatically collected by a robot 100,which can use its onboard sensors (150, 110) to observe the facilityinfrastructure and automatically generate a map.

With reference to FIGS. 1A and 1B, the mobile manipulation robots 100may have a set of sensors (150, 110) that enable autonomous navigationwithin a facility and sensors 110 that allow it to identify and localizeindividual SKUs for picking. The sensors (150, 110) may be 3D depthcameras, color cameras, laser ranging devices, or any combinationthereof. These sensors (150, 110) may provide high resolution 3D pointdata to the manipulation robot 100 that details the presence of physicalobjects within the sensors (150, 110) field of view. The sensors (150,110) may be connected to the onboard computer processor 718, which mayprocess the 3D point and color data to extract information fornavigation and picking. Alternatively, a unique set of sensors mountedon the manipulation robot 100 may be used for picking and fornavigation. The manipulation robot may be programmed to point thesensors in a direction that is expected for the task.

In order to perform pick work, the mobile manipulation robots 100 maymove and navigate between pick locations in the work zone 830 and anorder transfer area 860 (see FIG. 8). During navigation the sensor datamay be processed by the onboard computer processor 718 in a navigationsoftware module 712 to extract two modalities of information. The firstmodality may be local mapping information that indicates which areasaround the mobile manipulation robot 100 are traversable and which areascontain obstacles. The ground facing sensors 150 on the manipulationrobot 100 are primarily used to generate this mapping information. Theremay be two ground facing sensors 150, a front-facing one and arear-facing one. This unique design allows the mobile manipulation robot100 to navigate while driving both forwards and backwards, which incertain picking scenarios, eliminates the need for the manipulationrobot 100 to turn around, thus reducing travel time and increasingpicking efficiency.

The second sensor information modality may be visual or audible landmarklocations. According to the presently disclosed invention, the systemmay use landmarks such as visual markers, which may be placed ahead oftime in fixed locations around the facility of operation. At least oneof the onboard sensors (150, 110) may be used to detect these markersand locate the mobile manipulation robot 100 relative to them. Thisenables the robot 100 to know precisely where it is in the facility.Each marker may have a unique pattern that is different from othermarkers within the same facility. The unique marker pattern may berecognized by navigation module 712 algorithms which may be run by theonboard computer processor 718, thus allowing the mobile manipulationrobot 100 to localize itself without ambiguity.

Exemplary landmarks include visual markers as described above, which mayinclude any identifiable unique visual pattern, such as bar codes,numbers, letters, geometric shapes, or even a specific pattern ofblinking lights, and audible markers, which may include at least uniquepatterns of sound or even specific tones of sound. Before a robot canuse landmarks for navigation, the characteristics of the landmarks maybe stored on the central server 700 or on the remote storage 716 of therobot. When the characteristics of the landmarks are stored on theremote storage 716 of the mobile manipulation robot 100, the robot maynavigate autonomously through a logistics facility and may not requireconstant communication from the central server 700.

Additionally, careful attention may be given to the placement ofmarkers, which may be vertically mounted on shelving 810. This allowsthe robot 100 to locate vertically mounted visual markers, because theyare within the field of view of its arm mounted sensor 110. Verticallymounted markers are desirable because markers installed on the floor ofa facility are more difficult to maintain. Floor markers are subject totread damage from people and machines within the facility and thereforeneed more frequent maintenance.

In addition to onboard sensors (150, 110) and navigation software 712,the navigation process may also be aided by the central server 700. Theserver 700 may have access to the central facility map storage 754,which enables it to analyze the stored maps in depth and optimize routesbetween pick locations. As such, the central server 700 has a set ofroute planning algorithms in a software module 722 that allow it topre-compute navigation routes within the robot work zone 830, andbetween the work zone 830 and any transfer areas 860. These routes canbe stored after computation in a route storage database 752 within thecentral server 700, so that they can quickly be recalled andcommunicated to mobile manipulation robots 100, for rapid responseduring order fulfillment and for interchangeability between multiplerobots 100.

To perform individual piece picks, onboard sensors (150, 110) may beused to detect and localize individual pieces along with the specificlocations and orientations of the grasp points on the surface of apiece. During a pick, the sensors 110 also locate the infrastructurearound the pieces such as shelving levels, rack columns, shelf faces andsignage. This geometry information for the infrastructure is requiredfor pick manipulation algorithms in a manipulation software module 714to determine a pick trajectory that is collision free, such that themobile manipulation robot 100 is able to grasp the piece withoutcolliding with surrounding objects.

Special attention has been given to the placement of the pickingperception sensors 110, which are mounted on the manipulator arm 120 inan orientation that allows them to see the pick location while the endeffector 175 is positioned above the storage bed 140, as is shown inFIG. 1B. This method enables the system to localize additional pickpieces, grasp positions and orientations after a pick has been made andan item is being placed into the storage bed 140. This picking geometryinformation can be stored in memory 756, on the central server 700, or,and also, on the local storage 716 where it can be recalled later toenable sufficiently fast picks of the same SKU the next time it isrequired. Additionally, it is common for more than a single item of aparticular SKU to be picked for an order. In this case, the perceptionand localization computation of additional pick items can be done at thesame time the manipulator arm 120 is placing a previous pick in thestorage bed 140, which may help to improve the speed and efficiency ofpicking multiple items which are in near proximity.

An additional “fine tuning” sensor may be added to the robot near theend effector tool 175 to help accurately perform a pick grasp. After thepicking sensor 110 positively identifies and localizes a pick point,there may still be some positioning error present due to uncertainty inaccuracy and calibration of the sensor 110. Therefore, a tuning sensormay be mounted at the tip of the end effector tool 175 on the robot 100to more precisely locate the position of the tool 175 relative to thedesired pick location. The tuning sensor would have the desired picklocation in its field of view as the robot is attempting the pick grasp.As the manipulator arm 120 moves towards the desired pick location, thetuning sensor could be used to make small adjustments that guide thetool 175 toward the desired point.

The manipulator robots 100 have a mobile base 160 that is controlled bythe onboard computer processor 718. The mobile base may have two maindrive wheels 167, each driven by a servo motor. Each drive wheel 167 mayhave an encoder that provides motion feedback, which can be used toprecisely control the speed of each wheel in order to achieve thedesired rotation and translation velocities of the robot 100. Thefeedback data may also be used for odometry to estimate the motion ofthe robot 100 relative to the facility. The odometry may be responsiblefor guiding the robot 100 navigation at times when visual markers areout of sensor (150, 110) range. The mobile base 160 may also use passivewheels, such as casters 165, for stability and weight distribution.

All systems onboard the manipulator robot 100 may be powered fromonboard batteries 190, which may be housed within the mobile base 160.The batteries 190, such as the field replaceable battery detailedherein, may supply power to the robot during navigation and picking fora limited time, and may be rechargeable to maintain operation through aneconomically viable work period. Battery charging may occur separatelyfrom the mobile manipulation robot 100, wherein a partially or fullydischarged field replaceable battery may be swapped with separatelycharged field replaceable batteries for continued operation of the robot100.

In a logistics facility, the mobile manipulation robot 100 may have adesignated area of the facility 840 for recharging (see FIG. 8). Forexample, one or more docking stations and field replaceable batteriesmay be stored in the area, where they may also be recharged. A mobilemanipulation robot having a partially or almost fully discharged fieldreplaceable battery may navigate to the area 840, and a battery hot-swapmay be performed by using permanently installed smaller short-life(minutes) onboard batteries, such as the backup battery 575 shown inFIG. 5B, to maintain power while the field replaceable battery 400 isreplaced with a fully charged field replaceable battery. This preventsthe mobile manipulation robot 100 from needing to power down duringbattery swap, which saves time. Hot-swapping may be done manually by ahuman operator, or may be done automatically by internal mechanisms ofthe mobile manipulation robot 100 and charging station being used tophysically swap batteries 190 while the robot 100 coordinates theprocedure.

While specific embodiments of the invention have been described indetail, it should be appreciated by those skilled in the art thatvarious modifications and alternations and applications could bedeveloped in light of the overall teachings of the disclosure.Accordingly, the particular arrangements, systems, apparatuses, andmethods disclosed are meant to be illustrative only and not limiting asto the scope of the invention. For example, while both the fieldreplaceable battery and the lift counterbalance systems have beendescribed with reference to their uses in a mobile manipulation robot,they may easily find use in other systems and devices as would beunderstood by someone of ordinary skill in the art.

What is claimed is:
 1. A field replaceable battery comprising: at leastone battery cell; a main body configured to contain therein the at leastone battery cell; means to enable movement of the field replaceablebattery, wherein the means are attached to a bottom of the main body; acharging interface for connecting the at least one battery cell to anexternal power source; a blind mate connector electrically connected tothe at least one battery cell and configured to engage a correspondingblind mate connector on a battery powered device; and a connection meansangled with respect to the longitudinal axis of the main body, whereinthe angle is upward from a front end to a back end of the main body tolift the field replaceable battery into an engaged position onconnection with the battery powered device, wherein the engaged positionprovides electrical connection between the blind mate connector on thefield replaceable battery and the corresponding blind mate connector onthe battery powered device.
 2. The field replaceable battery of claim 1,wherein the connection means are configured to engage complementarydevice connection means in a cavity of the battery powered device. 3.The field replaceable battery of claim 2, wherein the connection meansare positioned on each of a left and a right side of the main body toengage the complementary device connection means positioned on an innerright side and an inner left side of the cavity.
 4. The fieldreplaceable battery of claim 2, wherein one of the device connectionmeans or the connection means is a rail and the other of the deviceconnection means or the connection means is a set of wheels configuredto engage the rail.
 5. The field replaceable battery of claim 1, furthercomprising: a locking handle having a locked position and an unlockedposition, wherein the locked position is configured to lock the fieldreplaceable battery in the engaged position on the battery powereddevice, and the unlocked position is configured to allowed movement ofthe field replaceable battery within the cavity of the battery powereddevice.
 6. The field replaceable battery of claim 1, further comprising:a charge sensor configured to sense a charge state of the at least onebattery cell; and a circuit electrically connected to the charge sensorfor receiving a signal indicative of the charge state of the at leastone battery cell.
 7. The field replaceable battery of claim 1, whereinthe means to enable movement of the field replaceable battery comprisesfixed casters, rotating casters, or a combination thereof.
 8. The fieldreplaceable battery of claim 6, further comprising a cover on the mainbody configured to provide access to an internal compartment of the mainbody comprising the at least one battery cell, the charge sensor, andthe circuit.
 9. The field replaceable battery of claim 1, wherein theexternal power source comprises a wired charging station, a wirelesscharging station, a direct connection to an AC power source, or acombination thereof.
 10. A power system for a mobile robot, the systemcomprising: a field replaceable battery comprising: at least one batterycell, a main body configured to contain therein the at least one batterycell, means to enable movement of the field replaceable battery, whereinthe means are attached to a bottom of the main body, a charginginterface for connecting the at least one battery cell to an externalpower source, a blind mate connector electrically connected to the atleast one battery cell and configured to engage a corresponding blindmate connector on a battery powered device, and a connection meansangled with respect to the longitudinal axis of the main body, whereinthe angle is upward from a front end to a back end of the main body tolift the field replaceable battery into an engaged position onconnection with the mobile robot; and a backup battery configured toprovide power to the mobile robot when the field replaceable battery isremoved or fully discharged, wherein the mobile robot comprises a mobilebase comprising a cavity configured to accept the field replaceablebattery, and wherein the engaged position provides electrical connectionbetween the blind mate connector on the field replaceable battery and acorresponding blind mate connector on the mobile robot.
 11. The powersystem of claim 10, wherein the cavity of the mobile robot comprises: adevice connection means positioned on an inner right side of the cavityand configured to engage a connection means on a right side of the mainbody of the field replaceable battery; and a device connection meanspositioned on an inner left side of the cavity and configured to engagea connection means on a left side of the main body of the fieldreplaceable battery.
 12. The power system of claim 12, furthercomprising: a charge sensor configured to sense a charge state of the atleast one battery cell; and a circuit electrically connected to thecharge sensor for receiving a signal indicative of the charge state ofthe at least one battery cell, wherein the memory of the mobile robotcomprises computer program instructions executable by the one or morerobot processors to receive the charge state of the at least one batterycell and alter a work task or a navigation path based on the chargestate of the at least one battery cell.
 13. A mobile robot comprising: amobile base; a field replaceable battery comprising: at least onebattery cell, a main body configured to contain therein the at least onebattery cell, means to enable movement of the field replaceable battery,wherein the means are attached to a bottom of the main body, a charginginterface for connecting the at least one battery cell to an externalpower source, a blind mate connector electrically connected to the atleast one battery cell and configured to engage a corresponding blindmate connector on the mobile base, and a battery connection means angledwith respect to the longitudinal axis of the main body, wherein theangle is upward from a front end to a back end of the main body to liftthe field replaceable battery into an engaged position on connectionwith the mobile base, wherein the engaged position provides electricalconnection between the blind mate connector on the field replaceablebattery and a corresponding blind mate connector on the mobile base; atleast one manipulator arm; a plurality of sensors; a memory; and one ormore robot processors coupled to the plurality of sensors, the memory,the mobile base, and the at least one manipulator arm, wherein thememory comprises computer program instructions executable by the one ormore robot processors to process data received from each of theplurality of sensors, and output control signals to the mobile base andthe at least one manipulator arm.
 14. The mobile robot of claim 13,wherein the mobile base comprises a cavity configured to accept thefield replaceable battery, the cavity comprising: a device connectionmeans positioned on an inner right side of the cavity and configured toengage a battery connection means on a right side of the main body ofthe field replaceable battery; and a device connection means positionedon an inner left side of the cavity and configured to engage a batteryconnection means on a left side of the main body of the fieldreplaceable battery, wherein the device connection means are angledupward from a front to a back of the cavity so that engagement with thebattery connection means on each of the left and the right side of themain body of the field replaceable battery lift the field replaceablebattery into the engaged position.
 15. The mobile robot of claim 13,wherein the at least one manipulator arm comprises a first end portionpivotally carried by the mobile base, a second end portion comprising anend effector, and an extension tool positioned at or near the second endportion and configured to provide access to an object withoutinterference from surrounding objects or infrastructure within alogistics facility.
 16. The mobile robot of claim 13, further comprisinga vertical actuator stage configured to raise and lower relative to themobile base, the at least one manipulator arm having a first end portionmounted on the vertical actuator stage and a second end portioncomprising an end effector.
 17. The mobile robot of claim 13, whereinthe field replaceable battery comprises a charge sensor configured tosense a charge state of the at least one battery cell, and a circuitconnected to the charge sensor for receiving a signal indicative of thecharge state of the at least one battery cell.
 18. The mobile robot ofclaim 17, wherein the memory further comprises computer programinstructions executable by one or more robot processors to receive thesignal from the circuit indicative of the charge state of the at leastone battery cell and send data to the central server.
 19. The mobilerobot of claim 13, wherein the field replaceable battery furthercomprises a locking handle having a locked position and an unlockedposition, wherein the locked position is configured to lock the fieldreplaceable battery in the engaged position on the mobile base, and theunlocked position is configured to allowed movement of the fieldreplaceable battery within the cavity of the mobile base.
 20. The mobilerobot of claim 13, further comprising: a backup battery configured toprovide power to the mobile robot when the field replaceable battery isremoved or fully discharged.